This invention relates to post drivers, and in particular, pertains improvements in the bearing relationship of the various operating components incorporated within the post driver to sustain its useful and effective life.
Post drivers typically include a base which is mounted to a tractor, normally by means of a three-point hitch. The post driver and its associated drive means, whether it be a hydraulically operated driver, pneumatically functioned, or mechanically actuated, generally include a base or carriage means that connects through a three-point hitch means to the tractor, and incorporates a driving ram thereon that reciprocates during functioning to provide repeat ramming of the post into ground, during its usage and application.
In the normally constructed post driver, the relationship between the driving ram, and its mounting upon the carriage, normally is provided through a bearinged relationship, and usually incorporating roller bearings, or a plurality of the same, are secured to the driving ram, and ride within channels formed to either side of the carriage means, so as to provide near frictionless shifting of the ram, during its reciprocal vertical movements while pounding upon the post, when driving it into the ground. As can be readily understood, the bearing contact between each roller, or a plurality of them, and the internal surfaces of the flanges forming the shaped channels provided integrally to either side of the carriage means, is just a line contact. It has been known, through many years of usage, that providing a bearing relationship between these operating components for a post driver, when tremendous forces and impacting pressures are exerted upon the bearings, during performance of the ramming function, generally leads towards deterioration at this interconnection between the carriage and its ram. Usually, the flanges of the carriage eventually become distorted, or bent out of shape, which leads towards looseness between the ram, and the carriage, during functioning, which cannot only lead to inaccuracy in driving of the post, but can also eventually cause a breakdown in the components, which may be hazardous, eventually, to the operator, and anyone in the vicinity nearby. Thus, the line-to-line contact on the channel flanges, through the bearing rollers of the prior art, is just too great of a concentration of the full load of impact exerted by the post driver on its operating components during sustained usage. Hence, the current invention is designed to alleviate this problem, by providing substantially sized bearing blocks as the means for providing a form of sliding engagement between the driving ram, and its carriage means, so as to spread out or disseminate that transfer of force between these components, while driving of a post, and eliminate that full load concentration as previously experienced during usage of the prior art type of post drivers.